MPI_SIZEOF No matching specific subroutine for this generic subroutine call

[Jack_S_1]

Given the following fortran code:

integer, parameter :: double = kind(1.0d0)

integer :: integerTest
real(double) :: doubleTest
complex(double) :: complexTest
integer :: testSize
integer :: ierr

integerTest = 0
doubleTest = real(0.d0, kind=double)
complexTest = cmplx(0.d0, 0.d0, kind=double)

call MPI_SIZEOF(integerTest, testSize, ierr)
! ...
call MPI_SIZEOF(doubleTest, testSize, ierr)
! ...
call MPI_SIZEOF(complexTest, testSize, ierr)

I get the error:

error #6285: There is no matching specific subroutine for this generic subroutine call. [MPI_SIZEOF]

on the line

call MPI_SIZEOF(complexTest, testSize, ierr)

This code compiles and executes with no issue using openmpi. What is the cause of this error? It seems like it's looking for a specific match for the type of complexTest, but the whole point of MPI_SIZEOF is to work generically with nearly any type.

[Jack_S_1]

Nothing? My code seems to work in MPICH, too. It's Intel MPI that stands out. 

[Jack_S_1]

I should also mention that the code works if I declare complexTest as complex without a kind, but that doesn't help much, since I need double precision complex.

[Jack_S_1]

And it fails if I declare complexTest as plain double complex.

[Jack_S_1]

This appears to be a bug in Intel MPI. It looks like the double complex overload is missing. However, with credit to Vladimir F. at StackOverflow, the following solution works:

use iso_fortran_env
! ...
testSize = storage_size(complexTest) / character_storage_size

Incidentally, this whole exercise was to properly select the MPI data type to use. In all cases, test size was used in a call to

call MPI_TYPE_MATCH_SIZE(MPI_TYPECLASS_COMPLEX, mpiType, testSize, ierr)